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Five causes of compressor tripping

Compressor tripping refers to the disconnection of the compressor overload protector, which results in the shutdown of the compressor.It is usually caused by the following 5 causes

1,Start with pressure:


Because in screw air compressor , the minimum pressure valve fault or the blockage of relief system often occurs, which results in the compressor shutdown, the pressure still exists in the system

treatment

Check the pressure gauges of the air Compressor and vent the pressure before start the air Compressor

2,Excessive air end resistance


The excessive resistance of the nose will cause the start-up current of the compressor to be too large, that is, the compressor overload, which will lead to the tripping of the air switch.It is caused by the following 3 reasons:

  • (1) Lubricating oil has high viscosity.
  • (2) Coking of screw and star wheel in the nose (single screw compressor).
  • (3) Excessive amount of lubricating oil in the air end
  • treatment

  • (1) Check whether the head and motor can rotate freely, and according to the previous experience of turning, to determine whether the resistance of turning increases or not.(usually the low temp causes the problem)
  • (2) Oil coking in the screw compressor head is a common phenomenon when the oil products are poor or the temperature is high.Change the lubricate oil.
  • (3) The direct way to solve the problem of excessive lubricating oil in the engine head is to open the cover of the engine head, release some lubricating oil in the engine head, and repair or replace the oil-breaking valve at the same time.
  • air compressor tripping

    3,Faults in Electrical Devices


    The most direct and effective way to judge whether it is an electrical or mechanical fault is to separate the motor from the nose, that is, to remove the coupling/belt. Compressor control system with protective devices, such as no separation of protective devices, start compressor, motor immediately running, the control panel will show motor current about 40A, running 10 seconds after showing abnormal current, motor automatically stop running, because when detected current is greater than 10% of the maximum current or less than 90% of the minimum current, the protection unit will automatically shut down. In this way, it will be impossible to judge the cause of the unit failure. When the protection is switched off, the motor will run continuously for mechanical reasons; on the contrary, the same tripping phenomenon will occur.

  • (1) Due to the vibration and other reasons during the use of air switch, the shorter start-up time may also lead to instantaneous start-up tripping.
  • (2) Faults of electronic control system, such as false alarm of temperature probe, ultra-high temperature jump and alarm caused by malfunction of temperature relay and circuit breaker in high temperature environment.
  • 4, Failure of unloading valve


    The unloading valve is an important part of screw compressor. Its main function is to control the load and unload of the unit, that is, to control the air intake of the compressor.

  • (1) The unloading valve can not be fully closed.
  • (2) The unloading valve opens ahead of time
  • treatment

  • (1) After removing the air filter, if the intake baffle is stuck by mechanical impurities, the unit can be opened smoothly after cleaning; if the intake baffle is stuck on the guide rod, the guide rod is ground with sandpaper, and a small amount of grease is applied on the guide rod; if the unloading valve is seriously damaged, the unloading valve needs to be replaced.
  • (2) it is necessary to know the starting time of this kind of compressor more accurately. At the same time, according to the time when the unloading valve is opened compared with the starting time of the compressor, if the former is larger than the latter, it proves that the unloading valve is not opened ahead of time; on the contrary, the unloading valve is opened ahead of time.
  • 5, High Temperature Jump Caused by Lubricating Oi


    There is a temperature-sensing probe on the sliding spool of the temperature-controlled bypass valve, which controls the opening and closing of the spool and judges that the opening temperature of the temperature-controlled bypass valve is within 70 (+10). After long-term use, the efficiency of the probe decreases and it can not operate at the normal temperature point, so that the hot lubricating oil from the air compressor body can not be directly returned to the air compressor body through the cooling of the oil cooler, making the air compressor temperature lower. It can not be effectively controlled.

    treatment

    Check the Purity and Leakage of lubricating oil。Or change the lubricate oil


    In addition, the characteristics of high temperature jump caused by air cooler, water cooler, three filters and other faults are more obvious, so it is no longer mentioned. In a word, there are many reasons for the compressor to jump, and there are many causes. Only when we have a comprehensive understanding of the compressor operation principle and the function of components, can we prevent the compressor from jumping in the future